CAMBRIDGE, Mass.--(BUSINESS WIRE)--Genzyme,
a Sanofi company (EURONEXT: SAN and NYSE: SNY), today announced that
ENGAGE, the first Phase 3 trial of its investigational oral therapy,
eliglustat tartrate, in previously untreated patients with Gaucher
disease type 1, met its primary endpoint. Patients treated with
eliglustat tartrate had a statistically significant improvement in
spleen size at nine months, compared with placebo.

Spleen volumes in eliglustat tartrate treated patients decreased from
baseline by a mean of 28 percent versus a mean increase of two percent
in placebo patients, for an absolute difference of 30 percent
(p<0.0001). In addition, all secondary endpoints were met, including
improvements in hemoglobin levels and platelet levels, as well as liver
volumes compared with placebo-treated individuals.

The initial safety analysis from ENGAGE suggests that eliglustat
tartrate was well tolerated. There were no serious adverse events
reported in the primary analysis period and no clinically meaningful
differences in the related adverse events reported between the two
treatment groups.

“The efficacy and safety data from our ENGAGE trial are consistent with
what were observed in our Phase 2 study, continuing to suggest that
eliglustat tartrate is a potent, well tolerated oral compound that may
become a meaningful option for patients and physicians,” said Genzyme
President and Chief Executive Officer, David Meeker, M.D. “The
development of eliglustat tartrate has been underway for more than a
decade and is the largest clinical program ever focused on Gaucher
disease, demonstrating our ongoing commitment to innovation on behalf of
this community.”

Full results from the ENGAGE study are planned for presentation at the
Lysosomal Disease Network WORLD meeting, February 12-15, 2013, in
Orlando, Fla. Top-line data from Genzyme’s second Phase 3 trial, ENCORE,
are expected in early 2013.

The company is developing eliglustat tartrate, a capsule taken orally,
to provide a convenient treatment alternative for patients with Gaucher
disease type 1, and to provide a broader range of treatment options for
patients and physicians to achieve individual therapeutic goals.
Currently, Genzyme’s Cerezyme® (imiglucerase for injection),
the standard of care for patients with Gaucher disease type 1, is
administered through intravenous infusions.

ENGAGE is a randomized, double-blind, placebo controlled study in
treatment-naïve patients with Gaucher disease type 1 and evaluated the
efficacy, safety and pharmacokinetics of twice-daily dosing of
eliglustat tartrate in 40 patients untreated for at least six months.
The study had a primary efficacy endpoint of improvement in spleen size
in individual patients treated with eliglustat tartrate compared with
treatment with placebo, after the nine month study period. Patients were
stratified at baseline by their spleen volume. Thirty-nine out of 40
study participants completed at least nine months of treatment. One
patient in the eliglustat treated group discontinued at six months for
personal reasons. At the end of nine months, patients who were on
placebo were transitioned to eliglustat tartrate. After the primary
analysis period concluded, all 39 patients chose to remain on treatment.
Eighteen medical centers in 12 countries in North America, South
America, Europe, Asia and the Middle East are participating in this
study.

Genzyme previously reported that the 12-month Phase 2 trial had met its
primary composite endpoint: a clinically meaningful response in at least
two of three endpoints (improvements in spleen size, hemoglobin and
platelet levels) in individual patients. All patients in the ongoing
Phase 2 trial have been on treatment for at least five years.

Genzyme is currently completing the second Phase 3 study, ENCORE. ENCORE
is a randomized, open-label study for adult patients with Gaucher
disease type 1, designed to compare eliglustat tartrate to Cerezyme.
One-hundred sixty adult patients were enrolled in this trial. A third
trial, known as EDGE is also fully enrolled, and compares once-daily
with twice-daily dosing of eliglustat tartrate. Combined, these trials
represent the largest clinical program ever focused on Gaucher disease,
with participating sites in over 30 countries. In total, more than 370
patients are enrolled in these studies.

About Gaucher disease

Gaucher disease is an inherited condition affecting fewer than 10,000
people worldwide. People with Gaucher disease do not have enough of an
enzyme, β-glucosidase (glucocerebrosidase) that breaks down a certain
type of fat molecule. As a result, lipid engorged cells (called Gaucher
cells) amass in different parts of the body, primarily the spleen, liver
and bone marrow. Accumulation of Gaucher cells may cause spleen and
liver enlargement, anemia, excessive bleeding and bruising, bone disease
and a number of other signs and symptoms. The most common form of
Gaucher disease, type 1, generally does not affect the brain.

About eliglustat tartrate

Eliglustat tartrate, a novel glucosylceramide analog given orally, is
designed to partially inhibit the enzyme glucosylceramide synthase,
which results in reduced production of glucosylceramide.
Glucosylceramide is the substance that builds up in the cells and
tissues of people with Gaucher disease. In preclinical studies, the
molecule, developed with James A. Shayman, MD, from the University of
Michigan, has shown high potency and specificity. Based on its mechanism
of action, which is independent of genotype, eliglustat tartrate may be
a potential therapy for all patients with Gaucher disease type 1.
Initiation of the Phase 2 and 3 studies of eliglustat tartrate in
Gaucher disease followed an extensive pre-clinical research effort and a
Phase 1 program.

Cerezyme important safety information

Approximately 15 percent of patients have developed IgG antibodies to
the infused enzyme. These patients have a higher risk of
hypersensitivity reaction. Therefore periodic monitoring is suggested;
caution should be exercised in patients with antibodies or prior
symptoms of hypersensitivity. Symptoms suggestive of hypersensitivity
occurred in 6.6 percent of patients, and include anaphylactoid reaction,
pruritus, flushing, urticaria, angioedema, chest discomfort, dyspnea,
coughing, cyanosis and hypotension. Reactions related to Cerezyme
administration have been reported in less than 15 percent of patients.
Each of the following events occurred in less than two percent of the
total patient population. Reported adverse events include nausea,
vomiting, abdominal pain, diarrhea, rash, fatigue, headache, fever,
dizziness, chills, backache and tachycardia. Adverse events associated
with the route of administration include discomfort, pruritus, burning,
swelling or sterile abscess at the site of venipuncture. For full
prescribing information, please visit www.genzyme.com.

About Genzyme, a Sanofi Company

Genzyme has pioneered the development and delivery of transformative
therapies for patients affected by rare and debilitating diseases for
over 30 years. We accomplish our goals through world-class research and
with the compassion and commitment of our employees. With a focus on
rare diseases and multiple sclerosis, we are dedicated to making a
positive impact on the lives of the patients and families we serve. That
goal guides and inspires us every day. Genzyme’s portfolio of
transformative therapies, which are marketed in countries around the
world, represents groundbreaking and life-saving advances in medicine.
As a Sanofi company, Genzyme benefits from the reach and resources of
one of the world’s largest pharmaceutical companies, with a shared
commitment to improving the lives of patients. Learn more at www.genzyme.com.

About Sanofi

Sanofi, a global and diversified healthcare leader, discovers, develops
and distributes therapeutic solutions focused on patients’ needs. Sanofi
has core strengths in the field of healthcare with seven growth
platforms: diabetes solutions, human vaccines, innovative drugs,
consumer healthcare, emerging markets, animal health and the new
Genzyme. Sanofi is listed in Paris (EURONEXT: SAN) and in New York
(NYSE: SNY).

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